Project Summary and Relevance: The Adolescent Trials Unit at The Children's Hospital of Philadelphia seeks to continue their work with the Adolescent Trials Network for HIV/AIDS Interventions. The site will conduct clinical studies developed or co-endorsed by the ATM that will focus on the following: 1) primary prevention through the Connect to Protect project. 2) secondary prevention through ATM clinical studies including both behavioral and biomedical interventions. 3) tertiary prevention through ATN clinical studies including therapeutic and behavioral trials targeting infected, ill youth. The site will accomplish these goals as follows. The Connect to Protect Project will continue to build community mobilization and partnerships through participation in ATN 016B, ATN 040,and other C2P specific studies. To address the second and third aims, the site will recruit and retain HIV-infected and at-risk youth into clinical trials. To accomplish this goal successfully, the site will continue with their targeted outreach and linkage program to identifyHIV- infected youth and link them to care. The site will provide a broad array of targeted, multidisciplinary services to support youth once engaged in research. The site PI will continue to work with the TLG to develop and implement the therapeutic agenda of the Network. Other staff will support the research agenda through participation on protocol teams. Finally, the site will contribute to the Network management through active participation in conference calls and meetings. This project addresses the epidemic of HIV infection in adolescents and young adults to provide the much needed scientific data to prevent new infections and maintain the health of those infected. The data from the clinical trials developed and implemented by the ATN will contribute significantly to understanding better ways to treat HIV infection in adolescents and prevent new infections from occurring. Relevance: This project will have major public health implications. Through well designed targeted clinical trials, the much needed data will be collected to learn better how to prevent the spread of new HIV infections in adolescents and young adults. The trials with HIV-infected adolescents and young adults will provide data required to prevent the spread of HIV from infected persons through better management strategies for infected individuals. .